Gamma sterilization using Co60, which is a radioisotope of Co, as a radiation source has been common for many years as a radiation sterilization method of containers used for food, beverages, drugs, cosmetics, and the like. Other radiation sterilization methods include treatment by X-rays or electron beams. The radiation sterilization has been widely spreading as a sterilization treatment method because containers can be treated at a low temperature, in a short time, and at a relatively low cost.
On the other hand, for the purpose of preventing oxygen oxidation of various articles liable to change in quality or deteriorate in response to the influence of oxygen, which are typified by food, beverages, drugs, and cosmetics, to thereby store them for a long period of time, there has been used an oxygen absorber to remove oxygen in a package containing these articles.
Further, there have been developed oxygen-absorbing resin compositions each containing a transition metal catalyst and a polymer having a predetermined tetralin ring and multilayer containers using the same (refer to Patent Literatures 1 to 3).